Compressor housing

Abstract

Disclosed is a compressor housing and method of assembling. The compressor housing may comprise an outer volute, a cavity, an impeller cover, a compressor diffuser and an inner volute. The outer volute includes a back wall and a curved casing. The back wall may include a receptacle and a first plurality of annular steps. The receptacle configured to receive an alignment pin. The cavity is configured to receive the compressor impeller and is at least partially defined by the back wall of the outer volute and the impeller cover. The impeller cover is configured to fragment during impact with the compressor impeller during a failure condition of the compressor impeller. The impeller cover is disposed between the inner volute and the cavity. The compressor diffuser is disposed between the back wall and the impeller cover.

What is claimed is: 
     
       1. A compressor housing for a turbocharger that includes a rotatable compressor impeller having a bore therethrough, the compressor housing comprising:
 an outer volute configured to be disposed about the bore, the outer volute including a back wall and a curved casing, the curved casing defining an airflow-passageway, the back wall extending radially inward from the curved casing, the back wall including a receptacle and a first plurality of annular steps, the receptacle configured to receive an alignment pin that positions a compressor diffuser in the compressor housing; 
 a cavity at least partially defined by the back wall of the outer volute and an impeller cover, the cavity configured to receive the compressor impeller; 
 the impeller cover configured to fragment during impact with the compressor impeller during a failure condition of the compressor impeller, the impeller cover disposed between an inner volute and the cavity; 
 the compressor diffuser disposed between the back wall and the impeller cover, the compressor diffuser including an annular body, a plurality of fins and the alignment pin, the fins disposed between the annular body and the impeller cover, the alignment pin disposed in the receptacle of the back wall of the outer volute; and 
 the inner volute disposed between the outer volute and the impeller cover, the inner volute including a bridge and an inner ring, the bridge extending between a first end and a second end of the impeller cover, the bridge and the impeller cover defining a chamber, the inner ring and the bridge and the impeller cover defining a pocket-void disposed inside the chamber. 
 
     
     
       2. The compressor housing of  claim 1 , in which the back wall of the outer volute further includes an annular groove configured to receive a balance ring that projects outward from a back surface of the compressor impeller, the annular groove configured to be spaced apart from the balance ring. 
     
     
       3. The compressor housing of  claim 2 , in which the back wall of the outer volute further comprises a second plurality of annular steps, wherein the annular groove is disposed between the first plurality of annular steps and the second plurality of annular steps. 
     
     
       4. The compressor housing of  claim 3 , wherein the annular groove, the first plurality of annular steps, and the second plurality of annular steps are disposed in a front surface of the back wall, the front surface adjacent to the cavity. 
     
     
       5. The compressor housing of  claim 2 , wherein the impeller cover is made of a frangible metal. 
     
     
       6. The compressor housing of  claim 5 , in which the compressor housing further includes an insert disposed in the cavity, the insert disposed to be proximal to a nose end of the compressor impeller. 
     
     
       7. The compressor housing of  claim 1 ,
 in which the annular body includes a back side, and 
 in which the back wall includes a front surface, and 
 the compressor housing further comprising: 
 a first side gap disposed between the back side of the annular body and the front surface of the back wall. 
 
     
     
       8. The compressor housing of  claim 7 ,
 in which the curved casing includes a base end, 
 in which the annular body further includes an inner side and an outer side radially outward of the inner side, and 
 the compressor housing further comprises a base gap disposed between the base end and the outer side of the annular body. 
 
     
     
       9. A method of assembling a compressor housing for a turbocharger that includes a rotatable compressor impeller including a bore therethrough, the method including:
 disposing an outer volute about the bore, the outer volute including a back wall and a curved casing, the curved casing defining an airflow-passageway, the back wall extending radially inward from the curved casing, the back wall including a receptacle and a first plurality of annular steps, the receptacle configured to receive an alignment pin that positions a compressor diffuser in the compressor housing; 
 arranging the back wall of the outer volute and an impeller cover to at least partially form a cavity configured to receive the compressor impeller, wherein the impeller cover is disposed between an inner volute and the cavity, the impeller cover is configured to fragment during impact with the compressor impeller during a failure condition of the compressor impeller; 
 disposing the compressor diffuser between the back wall and the impeller cover, the compressor diffuser including an annular body, a plurality of fins and the alignment pin, the fins disposed between the annular body and the impeller cover, the alignment pin disposed in the receptacle of the back wall of the outer volute; and 
 disposing the inner volute between the outer volute and the impeller cover, the inner volute including a bridge and an inner ring, the bridge extending between a first end and a second end of the impeller cover, the bridge and the impeller cover defining a chamber, the inner ring and the bridge and the impeller cover defining a pocket-void disposed inside the chamber. 
 
     
     
       10. The method of  claim 9 , wherein the back wall of the outer volute further includes an annular groove configured to receive a balance ring that projects outward from a back surface of the compressor impeller, the annular groove configured to be spaced apart from the balance ring. 
     
     
       11. The method of  claim 10  in which the back wall further includes a second plurality of annular steps, wherein the annular groove, the first plurality of annular steps, and the second plurality of annular steps are disposed in a front surface of the back wall, the front surface adjacent to the cavity. 
     
     
       12. The method of  claim 9 ,
 wherein the annular body includes a back side, and 
 wherein the back wall includes a front surface, and 
 wherein the compressor housing further includes a plurality of side gaps disposed between a back side of the annular body and the front surface of the back wall. 
 
     
     
       13. A turbocharger that includes:
 a rotatable turbocharger shaft; 
 a compressor impeller disposed in a cavity and mounted via a stud coupled to the rotatable turbocharger shaft, the compressor impeller including a nose end, a hub end and a plurality of blades disposed between the nose end and the hub end, each blade having a rim; and 
 a compressor housing comprising:
 an outer volute arranged about the stud, the outer volute including a back wall and a curved casing, the curved casing defining an airflow-passageway, the back wall extending radially inward from the curved casing, the back wall proximal to and spaced apart from the compressor impeller, the back wall including a receptacle and a first plurality of annular steps, the receptacle configured to receive an alignment pin that positions a compressor diffuser in the compressor housing; 
 the cavity at least partially defined by the back wall of the outer volute and by an impeller cover; 
 the impeller cover configured to fragment during impact with the compressor impeller during a failure condition of the compressor impeller, the impeller cover disposed between an inner volute and the compressor impeller; 
 the compressor diffuser disposed between the back wall and the impeller cover, the compressor diffuser including an annular body, a fin and the alignment pin, the fin extending from the annular body to the impeller cover, the alignment pin disposed in the receptacle of the back wall of the outer volute; 
 the inner volute disposed between the outer volute and the impeller cover, the inner volute including a bridge and an inner ring, the bridge extending from a first end to a second end of the impeller cover, the bridge and the impeller cover defining a chamber, the inner ring and the bridge and the impeller cover defining a pocket-void disposed inside the chamber. 
 
 
     
     
       14. The turbocharger of  claim 13 , in which the compressor impeller includes a balance ring and in which the back wall of the outer volute further comprises:
 a second plurality of annular steps; and 
 an annular groove disposed between the first plurality of annular steps and the second plurality of annular steps, wherein the balance ring is disposed in the annular groove. 
 
     
     
       15. The turbocharger of  claim 14 ,
 in which the curved casing includes a base end, and 
 in which the annular body includes a back side, and 
 in which the back wall includes a front surface, and 
 the compressor housing further comprising: 
 a plurality of side gaps disposed between a back side of the annular body and the front surface of the back wall, wherein each of the side gaps are slit-like, 
 wherein the base end and the front surface of the back wall define a recess having a sidewall and a floor, wherein further the annular body is disposed in the recess to extend along the floor. 
 
     
     
       16. The turbocharger of  claim 13 , in which the back wall of the outer volute further comprises an annular groove, and in which the compressor impeller includes a balance ring extending toward the back wall, and in which the compressor impeller further comprises a bulge portion disposed between the balance ring and the hub end, wherein the bulge portion is disposed radially inward of the annular groove and is disposed between the annular groove and the hub end. 
     
     
       17. The turbocharger of  claim 16 ,
 in which the curved casing includes a base end, 
 in which the annular body further includes an inner side and an outer side radially outward of the inner side, and 
 the compressor housing further comprises a base gap disposed between the base end and the outer side of the annular body. 
 
     
     
       18. The turbocharger of  claim 17 , wherein the compressor housing further includes a blade gap disposed directly between the rim of each blade and the inner side of the annular body, the rim radially aligned with an inner corner of the inner side of the annular body, an outer corner of the inner side radially aligned with the first plurality of annular steps and free of radial alignment with the rim of each blade. 
     
     
       19. The turbocharger of  claim 13 , in which the compressor housing further includes an insert disposed in the cavity, the insert configured to be disposed proximal to a nose end of the compressor impeller. 
     
     
       20. The turbocharger of  claim 13  further comprising:
 a turbine housing connected to the compressor housing; 
 a turbine wheel rotatably disposed within the turbine housing and configured to be rotated by exhaust received from an engine, the turbine wheel operably connected to the compressor impeller.